Two phenolic compounds, methylkarranjic (1) acid and pongamol (2), were isolated from the petroleum ether soluble fraction of an ethanolic extract of Derris indica seeds. The structures of these compounds were confirmed by LC-MS and a series of 1D and 2D NMR data. The solvent solvent partionates of the ethanolic extract and compounds (1 and 2) exhibited moderate antibacterial activity against several test organisms. The minimum inhibitory concentrations (MICs) of 1 and 2 were found to be in the range of 32-128 μg/ml against Bacillus megatorium, Streptococcus β-haemolyticus, Shigella dysenteriae and E. coli. Key words: Derris indica; Leguminosae; Methylkarranjic acid; Pongamol; Antibacterial activity Dhaka Univ. J. Pharm. Sci. 6(1): 9-13, 2007 (June) The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website